My dad died, but signed titles to my aunt. Is the property mine or my aunts?

If he sign it to the aunt before he passed then it is hers. Was there any other documentation ?

Really need more detail here like where you are located. Under what circumstances title was signed over. etc. But unless you can show there was something wrong with his signing over title the property belongs to whomever the title is listed to.

The name or names on a deed or title take precedence over a will.
If your father left 'everything' to you in his will, deeds and bank accounts and any property in the name of someone else don't count.